Chirp signal is a signal whose frequency changes over time. Such signal has been widely used in sonar, radar, spread spectrum communications, resonant converter, electronic ballast, and the like. However, at present, chirp signal is usually generated by using a phase-locked loop or an analog frequency synthesis method. When chirp signal is generated by using the phase-locked loop, an output frequency modulation mode cannot be precisely controlled, which results in deterioration of performance of the chirp signal. When chirp signal is generated by using the analog frequency synthesis method, it is required to use mixer and filter, which results in very high cost and impossibility to be implemented on a chip.
To cope with this, it is desirable to provide a signal generator and a signal generation method capable of generating a chirp signal with high accuracy and at a low cost.